US Patent 7255074 Linear EMV actuator using permanent magnet and electromagnet

A linear EMV actuator uses a permanent magnet and an electromagnet in which EMV operation for opening/closing an exhaust valve and an intake valve makes valve operations linear. As a result, the valve undergoes a soft landing and active control of an amount of opening of the valve. The linear EMV actuator includes an upper core and a lower core, an armature, an actuator spring and a valve spring. Also included are a permanent magnet, an upper coil and a lower coil connected to each other in series thereby forming one electromagnet, a displacement sensor, and a position controller.